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Remote state preparation and teleportation in phase space

Matteo G. A. Paris·Mary Cola·Rodolfo Bonifacio
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Abstract

Continuous variable remote state preparation and teleportation are analyzed using Wigner functions in phase space. We suggest a remote squeezed state preparation scheme between two parties sharing an entangled twin beam, where homodyne detection on one beam is used as a conditional source of squeezing for the other beam. The scheme works also with noisy measurements, and provide squeezing if the homodyne quantum efficiency is larger than 50%. Phase space approach is shown to provide a convenient framework to describe teleportation as a generalized conditional measurement, and to evaluate relevant degrading effects, such the finite amount of entanglement, the losses along the line, and the nonunit quantum efficiency at the sender location.

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Matteo G. A. Paris, Mary Cola, Rodolfo Bonifacio. 2003-01-21. Remote state preparation and teleportation in phase space. https://doi.org/10.1088/1464-4266/5/3/370

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